U.S. patent application number 15/543953 was filed with the patent office on 2018-01-25 for method for managing wireless resources, and access point using same.
This patent application is currently assigned to KT CORPORATION. The applicant listed for this patent is KT CORPORATION. Invention is credited to Mi-Ji CHOI, Yang-Seok JEONG, Jong-Hwa SHIN, Young-Keum SONG.
Application Number | 20180027552 15/543953 |
Document ID | / |
Family ID | 56406071 |
Filed Date | 2018-01-25 |
United States Patent
Application |
20180027552 |
Kind Code |
A1 |
JEONG; Yang-Seok ; et
al. |
January 25, 2018 |
METHOD FOR MANAGING WIRELESS RESOURCES, AND ACCESS POINT USING
SAME
Abstract
The present invention relates to a method for managing wireless
resources, and an access point (AP) using the same. The method for
managing wireless resources, according to one embodiment of the
present invention, can comprise: a monitoring step of monitoring
the use state of an operation channel being used, so as to
determine the use state of the wireless resources for the operation
channel; and a control step of changing, by the AP, the frequency
of the operation channel or handing a terminal connected to the AP
over to a neighboring AP according to the determined use state of
the wireless resources.
Inventors: |
JEONG; Yang-Seok;
(Gyeonggi-do, KR) ; SONG; Young-Keum; (Seoul,
KR) ; SHIN; Jong-Hwa; (Seoul, KR) ; CHOI;
Mi-Ji; (Gyeonggi-do, KR) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
KT CORPORATION |
Gyeonggi-do |
|
KR |
|
|
Assignee: |
KT CORPORATION
Gyeonggi-do
KR
|
Family ID: |
56406071 |
Appl. No.: |
15/543953 |
Filed: |
January 13, 2016 |
PCT Filed: |
January 13, 2016 |
PCT NO: |
PCT/KR2016/000357 |
371 Date: |
July 14, 2017 |
Current U.S.
Class: |
370/336 |
Current CPC
Class: |
H04W 36/22 20130101;
H04W 36/08 20130101; H04W 88/08 20130101; H04W 72/04 20130101; H04W
72/085 20130101; H04W 72/0486 20130101; H04W 72/082 20130101; H04L
69/22 20130101; H04W 84/12 20130101; H04W 72/0446 20130101; H04W
74/08 20130101; H04W 36/06 20130101; H04W 24/00 20130101; H04W
24/02 20130101 |
International
Class: |
H04W 72/04 20060101
H04W072/04; H04W 72/08 20060101 H04W072/08 |
Foreign Application Data
Date |
Code |
Application Number |
Jan 16, 2015 |
KR |
10-2015-0008176 |
Claims
1. A method for managing wireless resources, comprising: a
monitoring step of monitoring, by access point, a utilization
status of an operation channel being used, to determine a wireless
resource utilization state of the operation channel; and a control
step of changing, by the access point, frequency of the operation
channel or handing over station connected to the access point to a
nearby access point, based on the determined wireless resource
utilization state.
2. The method for managing wireless resources according to claim 1,
wherein the monitoring step comprises generating a wireless
resource utilization distribution matrix of the operation channel
based on a result of the monitoring.
3. The method for managing wireless resources according to claim 2,
wherein the monitoring step comprises generating the wireless
resource utilization distribution matrix containing separately a
busy time during which the operation channel is occupied and used,
and an idle time during which the operation channel is unoccupied
and stays idle waiting.
4. The method for managing wireless resources according to claim 3,
wherein the busy time comprises an interference time during which a
non-WLAN signal or an interfering signal occupies the operation
channel, an overlapping load time during which the nearby access
point occupies the operation channel, and a self-load time during
which the access point occupies the operation channel.
5. The method for managing wireless resources according to claim 4,
wherein the monitoring step comprises categorizing a time during
which a signal impossible to decode is inputted via the operation
channel as the interference time.
6. The method for managing wireless resources according to claim 5,
wherein the monitoring step comprises, when the signal impossible
to decode is inputted, performing energy detection on the operation
channel, and measuring a time during which detection of energy
higher than or equal to a preset energy limit in the operation
channel continues as the interference time.
7. The method for managing wireless resources according to claim 4,
wherein the monitoring step comprises calculating the overlapping
load time or the self-load time by summing up a time during which
the operation channel is occupied by the signal, when it is
possible to decode the signal inputted via the operation
channel.
8. The method for managing wireless resources according to claim 7,
wherein the monitoring step comprises identifying the time during
which the operation channel is occupied by the signal using a
duration value stored in a duration field included in a header
region of a Medium Access control (MAC) frame included in the
signal.
9. The method for managing wireless resources according to claim 8,
wherein the monitoring step comprises: calculating the overlapping
load time by summing up a duration value included in a signal with
a transmitter address or a receiver address included in the decoded
MAC header mismatching an address of the station connected to the
access point; and calculating the self-load time by summing up a
duration value included in a signal with a transmitter address or a
receiver address included in the decoded MAC header matching an
address of the station connected to the access point.
10. The method for managing wireless resources according to claim
4, wherein the monitoring step comprises generating the wireless
resource utilization distribution matrix by calculating an
interference ratio of the interference time to total monitoring
time, an overlapping load ratio of the overlapping load time to
total monitoring time, and a load ratio of the self-load time to
total monitoring time.
11. The method for managing wireless resources according to claim
10, wherein the control step comprises, when the interference ratio
exceeds a preset excessive interference ratio, determining it as
excessive interference and changing the operation channel of the
access point.
12. The method for managing wireless resources according to claim
10, wherein the control step comprises, when the overlapping load
ratio exceeds a preset overlapping ratio limit, determining it as
excessive overlapping load, and changing the operation channel of
the access point.
13. The method for managing wireless resources according to claim
10, wherein the control step comprises, when the load ratio exceeds
a preset load ratio limit, determining it as excessive self-load,
and handing over stations connected to the access point to the
nearby access point.
14. Access point comprising: a monitoring unit configure to monitor
a utilization status of an operation channel to determine a
wireless resource utilization state of the operation channel; and a
control unit configured to change the operation channel or hand
over a connected station to a nearby access point based on the
determined wireless resource utilization state.
Description
TECHNICAL FIELD
[0001] The present application claims priority to Korean Patent
Application No. 10-2015-0008176 filed in the Republic of Korea on
Jan. 16, 2015, the disclosure of which is incorporated herein by
reference.
[0002] The present disclosure relates to a method for managing
wireless resources and access point using the same, and more
particularity, to a wireless resource management method for
efficiently managing wireless resources used in a wireless local
area network (WLAN) system and access point using the same.
BACKGROUND ART
[0003] A wireless local area network (WLAN) basically supports
Access Point (AP) acting as the point of access in a Distributed
System (DS) and Basic Service Set (BSS) composed of multiple
wireless stations (STAs), not APs.
[0004] Generally, AP provides a service with a specific wireless
channel in unlicensed frequency bands set as an operation channel.
Thus, each AP may arbitrarily set operation channels, and adjacent
APs may work on the overlapping operation channel having the same
frequency. This is referred to as overlapping basic service set
(OBSS), and in OBSS environment, APs and STAs contend for the same
wireless channel resource. In this case, if a certain AP occupies
too much wireless resources, other APs experience a lack of
wireless resources, failing to efficiently manage wireless
resources.
[0005] Meanwhile, even when adjacent APs have different operation
channels, a certain AP may have a concentration of many STAs, while
a smaller number of STAs may be connected to nearby APs. In this
instance, the AP having a concentration of STAs experiences a lack
of wireless resources, resulting in reduced processing rate or WLAN
service quality degradation, whereas wireless resources are not
used by the nearby APs that can provide the same WLAN service,
causing an inefficient management problem.
DISCLOSURE
[0006] Technical Problem
[0007] The present disclosure is directed to providing a wireless
resource management method for efficiently managing wireless
resources used in a wireless local area network (WLAN) system and
access point using the same.
[0008] Technical Solution
[0009] A method for managing wireless resources according to an
embodiment of the present disclosure includes a monitoring step of
monitoring, by access point (AP), a utilization status of an
operation channel being used to determine a wireless resource
utilization state of the operation channel, and a control step of
changing, by the AP, frequency of the operation channel or handing
over station connected to the AP to a nearby AP, based on the
determined wireless resource utilization state.
[0010] Here, the monitoring step may include generating a wireless
resource utilization distribution matrix of the operation channel
based on a result of the monitoring.
[0011] Here, the monitoring step may include generating the
wireless resource utilization distribution matrix containing
separately a busy time during which the operation channel is
occupied and used, and an idle time during which the operation
channel is unoccupied and stays idle waiting.
[0012] Here, the busy time may include an interference time during
which a non-WLAN signal or an interfering signal occupies the
operation channel, an overlapping load time during which the nearby
AP occupies the operation channel, and a self-load time during
which the AP occupies the operation channel.
[0013] Here, the monitoring step may include categorizing a time
during which a signal impossible to decode is inputted via the
operation channel as the interference time.
[0014] Here, the monitoring step may include, when the signal
impossible to decode is inputted, performing energy detection on
the operation channel, and measuring a time during which detection
of energy higher than or equal to a preset energy limit in the
operation channel continues as the interference time.
[0015] Here, the monitoring step may include calculating the
overlapping load time or the self-load time by summing up a time
during which the operation channel is occupied by the signal, when
it is possible to decode the signal inputted via the operation
channel.
[0016] Here, the monitoring step may include identifying the time
during which the operation channel is occupied by the signal using
a duration value stored in a duration field included in a header
region of a Medium Access control (MAC) frame included in the
signal.
[0017] Here, the monitoring step may include calculating the
overlapping load time by summing up a duration value included in a
signal with a transmitter address or a receiver address included in
the decoded MAC header mismatching an address of the station
connected to the AP, and calculating the self-load time by summing
up a duration value included in a signal with a transmitter address
or a receiver address included in the decoded MAC header matching
an address of the station connected to the AP.
[0018] Here, the monitoring step may include generating the
wireless resource utilization distribution matrix by calculating an
interference ratio of the interference time to total monitoring
time, an overlapping load ratio of the overlapping load time to
total monitoring time, and a load ratio of the self-load time to
total monitoring time.
[0019] Here, the control step may include, when the interference
ratio exceeds a preset excessive interference ratio, determining it
as excessive interference and changing the operation channel of the
AP.
[0020] Here, the control step may include, when the overlapping
load ratio exceeds a preset overlapping ratio limit, determining it
as excessive overlapping load, and changing the operation channel
of the AP.
[0021] Here, the control step may include, when the load ratio
exceeds a preset load ratio limit, determining it as excessive
self-load, and handing over stations connected to the AP point to
the nearby AP.
[0022] The AP according to an embodiment of the present disclosure
includes a monitoring unit configure to monitor a utilization
status of an operation channel to determine a wireless resource
utilization state of the operation channel, and a control unit
configured to change the operation channel or hand over a connected
station to a nearby AP based on the determined wireless resource
utilization state.
[0023] In addition, the above technical problem-solving methods do
not enumerate all the features of the present disclosure. Various
features of the present disclosure and resulting advantages and
effects will be understood in greater detail with reference to the
following specific embodiments.
[0024] Advantageous Effects
[0025] According to the method for managing wireless resources in
accordance with an embodiment of the present disclosure and access
point using the same, it is possible to efficiently manage wireless
resources used in a wireless local area network (WLAN) system.
[0026] According to the method for managing wireless resources in
accordance with an embodiment of the present disclosure and access
point using the same, it is possible to monitor the wireless
resource utilization status of channels used in a WLAN system as a
quantitative indicator.
[0027] According to the method for managing wireless resources in
accordance with an embodiment of the present disclosure and access
point using the same, it is possible to prevent wireless resources
such as operation channels of access points from being excessively
occupied by signals transmitted from non-WLAN devices or signals
from overlapping another access point.
[0028] According to the method for managing wireless resources in
accordance with an embodiment of the present disclosure and access
point using the same, it is possible to determine whether stations
concentrate on a specific access point in a WLAN system, and in the
event of concentration of stations, to distribute loads to nearby
access points.
BRIEF DESCRIPTION OF DRAWINGS
[0029] FIGS. 1 and 2 are schematic diagrams showing a wireless
local area network (WLAN) system including access point according
to an embodiment of the present disclosure.
[0030] FIG. 3 is a block diagram showing access point according to
an embodiment of the present disclosure.
[0031] FIG. 4 is a timing diagram showing data frame transmission
between access point and station according to an embodiment of the
present disclosure.
[0032] FIG. 5 is a schematic diagram showing a wireless resource
utilization distribution matrix according to an embodiment of the
present disclosure. FIG. 6 is a flowchart showing a method for
managing wireless resources according to an embodiment of the
present disclosure.
MODE FOR CARRYING OUT THE INVENTION
[0033] Hereinafter, preferred embodiments are described in a manner
sufficiently clear and complete for them to be easily carried out
by those having ordinary skill in the technical field to which the
invention belongs, by referring to the accompanying drawings.
Rather, in describing the preferred embodiments of the present
disclosure in detail, when detailed descriptions of related known
functions or elements are deemed to render the essence of the
present disclosure ambiguous, their detailed descriptions are
omitted herein. Furthermore, parts having similar functions and
operation will be indicated by the same symbol throughout the
drawings.
[0034] In addition, throughout the specification, it will be
understood that when an element is referred to as being `connected`
to another element, it can he directly connected to the other
element or intervening elements may be prese contrast, when an
element is referred to as being `directly connected` to another
element, there are no intervening elements present. It will be
further understood that the terms `comprises`, `comprising`,
`includes` and/or `including` as used herein specify the presence
of stated elements, but do not preclude the presence or addition of
one or more other elements.
[0035] FIGS. 1 and 2 are schematic diagrams showing a wireless
local area network (WLAN) system including access point (AP)
according to an embodiment of the present disclosure.
[0036] As shown in FIG. 1(a), the WLAN system forms a basic service
set (BSS) in infrastructure mode enabling the wireless
interconnection of an AP and stations (STAs), and can provide a
local network service. Here, AP can provide a service using a
specific wireless channel in a service unlicensed frequency band
set as an operation channel #100. Thus, as in FIG. 1(b), to provide
a wireless local network service over a wide area using multiple
APs AP1, AP2, AP3, AP4, there is a need to set each AP to use
different operation channels #100, #112, #150. That is, the
wireless channel capacity can be maximized by setting the operation
channels between adjacent APs to different frequencies.
[0037] Because operation channels can be arbitrarily set, adjacent
APs AP1, AP2 may work on the overlapping operation channel #100
having the same frequency as shown in FIG. 2(a). This is referred
to as overlapping basic service set (OBSS), and in OBSS
environment, AP1, AP2 and STA1, STA2, STA3 contend for the same
wireless channel resource. In this case, if a certain access point
AP1, AP2 occupies too much wireless resources, the other access
point experiences a lack of wireless resources, failing to
efficiently manage wireless resources.
[0038] Furthermore, as in FIG. 2(b), even when adjacent access
points AP1, AP2 have different operation channels #100, #112, a
certain access point AP1 may have a concentration of many stations
STA1, STA2, STA3, STA4, STA5, while a smaller number of stations
STA6 may be connected to a nearby access point AP2. In this
instance, due to a lack of wireless resources, AP1 having a
concentration of stations has a reduction in processing rate or
WLAN service quality degradation, whereas wireless resources are
not used by the nearby access point AP2 that can provide the same
WLAN service, causing an inefficient management problem.
[0039] Meanwhile, in relation to a data transmission method in the
WLAN system, as shown in FIG. 4, STA1 may transmit a data frame to
AP, and AP may transmit an ACK frame to STA1 to notify that it has
received the corresponding data frame normally. Specifically,
before transmitting data, STA1 may identify whether an operation
channel is busy or idle during DCF InterFrame Space (DIFS). That
is, when Distributed Coordinate Function (DCF) is used as a channel
access mechanism in the WLAN system, it is required to identify the
state of the channel during DIFS before transmitting a data frame
or a management frame. Subsequently, when STA1 transmits a data
frame through the operation channel, AP may identify the state of
the channel during Short InterFrame Space (SIFS), and transmit a
control frame such as an Acknowledge (ACK) frame and a Clear To
Send (CTS) frame in response to the received data frame. According
to embodiments, to support Quality of Service (QoS), DIFS may be
replaced by Arbitration InterFrame Space (AIFS) having a variable
length based on the type of data traffic.
[0040] That is, when energy higher than or equal to a preset energy
limit is sensed in the operation channel during DIFS or SIFS, STA1
or AP determines that the operation channel is in busy state, and
waits for the release from the busy state. Later, when the
operation channel is released from the busy state, it identifies
the state of the operation channel during DIFS, and to prevent
collisions caused by simultaneous transmissions from other STA, it
performs backoff during Contention Window (CW) prior to
transmission. Here, although the case in which STA1 transmits data
to AP is taken as an example, the same method may be used in the
case in which AP transmits data to STA1.
[0041] Additionally, to prevent transmission collisions between
data frames and needing to stay awake and wait while other STA is
transmitting data, each of STA and AP may use a Network Allocation
Vector (NAV) timer. That is, a header region of a Medium Access
Control (MAC) frame transmitted with a data frame contains
information of the corresponding data frame including a transmitter
address and a receiver address and a duration field representing
the time to be protected to complete transmission. Thus, other STA
or AP sets an expiry time of each NAV timer to determine the time
to attempt to access the operation channel, by referring to the
duration field from the header of the MAC frame that was received
via the operation channel and decoded normally. Here, the duration
stored in the duration field may be set based on the length of the
data frame to transmit, SIFS and the length of an ACK frame, and
the expiry time of the NAV timer may be set as an expiry time of
the ACK frame. Accordingly, STA or AP does not need to always
identify whether the operation channel is busy or idle to transmit
a data frame, and wakes up and attempts to access the channel each
time the set NAV timer expires.
[0042] Hereinafter, by referring to the data transmission method in
the WLAN system described above, AP according to an embodiment of
the present disclosure capable of solving the inefficient wireless
resource utilization problem in the WLAN system is described.
[0043] FIG. 3 is a block diagram showing AP according to an
embodiment of the present disclosure.
[0044] Referring to FIG. 3, the AP according to an embodiment of
the present disclosure includes a monitoring unit 10 and a control
unit 20. The monitoring unit 10 and the control unit 20 may be
implemented as a combination of hardware and/or software.
Furthermore, the AP may include memory and at least one processor,
and functions of the monitoring unit 10 and the control unit 20 as
described below may be implemented in the AP in the form of a
program that is stored in the memory and executed by the at least
one processor.
[0045] The monitoring unit 10 may monitor the utilization status of
the operation channel used by AP during a preset monitoring time,
and determine the wireless resource utilization state of the
operation channel based on the monitoring results.
[0046] Specifically, the monitoring unit 10 may generate a wireless
resource utilization distribution matrix of the operation channel
based on the monitoring results. That is, as shown in FIG. 5, the
wireless resource utilization distribution matrix may represent a
busy time and an idle time. Here, the busy time is the time during
which the operation channel is occupied by a signal having energy
higher than or equal to a preset energy limit, and the idle time
corresponds to the time during which the operation channel is not
occupied by a signal having energy higher than or equal to the
preset energy limit and stays idle waiting. Here, the busy time may
be categorized into an interference time, an overlapping load time,
and a self-load time. The interference time refers to the time
during which the operation channel is occupied by a non-WLAN signal
or an interfering signal, and the overlapping load time refers to
the time during which nearby AP occupies the operation channel.
That is, the overlapping load time refers to the time during which
the operation channel is occupied by nearby AP when AP uses the
same operation channel as the nearby AP as shown in FIG. 2(a).
Meanwhile, the self-load time refers to the time during which AP
occupies the operation channel.
[0047] Here, the monitoring unit 10 may decode a signal inputted
via the operation channel, and if the signal is impossible to
decode, may determine the time during which the signal is inputted
to be the interference time. That is, because the non-WLAN signal
or interfering signal is impossible for AP to decode, when the
signal impossible to decode is inputted, the operation channel may
be determined to be occupied by the non-WLAN signal or interfering
signal. In this instance, the monitoring unit 10 may perform energy
detection on the operation channel, and may measure the time during
which detection of energy higher than or equal to the preset energy
limit continues and calculate the interference time. That is, the
monitoring unit 10 may calculate the interference time by summing
up the time during which detection of energy higher than or equal
to the preset energy limit continues over the total monitoring time
during which monitoring is performed. However, there is always a
non-WLAN signal or interfering signal applied to the operation
channel. Accordingly, only in the case in which the non-WLAN signal
or interfering signal has levels higher than or equal to the preset
energy limit, the operation channel is determined to be occupied by
the non-WLAN signal or interfering signal and impossible to
transmit another WLAND signal.
[0048] On the other hand, if the signal inputted via the operation
channel is possible to decode, the monitoring unit 10 may determine
that the operation channel is occupied by AP or nearby AP. Here,
the transmitter address or receiver address included in the header
region of the MAC frame included in the signal may be used to
identify whether the operation channel is occupied by nearby AP or
AP occupies the operation channel. That is, when the transmitter
address or receiver address included in the decoded MAC header
matches an address of STA connected to AP, AP may be determined to
occupy the operation channel, and when the addresses mismatch, the
operation channel may be determined to be occupied by nearby AP.
Subsequently, the duration value stored in the duration field
included in the header region of the MAC frame included in the
signal may be used to identify the time during which the operation
channel is occupied by the signal.
[0049] Accordingly, the monitoring unit 20 may calculate
respectively the self-load time during which AP occupies the
operation channel and the overlapping load time during which nearby
AP occupies the operation channel, using the transmitter address or
receiver address and the duration field of the signal. That is, the
monitoring unit 20 may calculate the overlapping load time by
summing up duration values included in signals with the transmitter
address or receiver address included in the decoded MAC header
mismatching the address of STA connected to AP. Furthermore, the
monitoring unit 20 may calculate the self-load time by summing up
duration values included in signals with the transmitter address or
receiver address included in the decoded MAC header matching the
address of STA connected to AP.
[0050] Additionally, the monitoring unit 10 may generate a wireless
resource utilization distribution matrix by calculating
respectively an interference ratio of the interference time to the
total monitoring time, an overlapping load ratio of the overlapping
load time to the total monitoring time, and a load ratio of the
self-load time to the total monitoring time. That is, the
monitoring unit 10 may generate the wireless resource utilization
distribution matrix by applying proportions of the ratios.
Meanwhile, the monitoring unit 10 may periodically calculate each
corresponding interference time, overlapping load time, and
self-load time in the total monitoring time.
[0051] The control unit 20 may change the operation channel or hand
over the connected STA to nearby AP, based on the determined
wireless resource utilization state. That is, the control unit 20
may distribute wireless resources based on the monitoring results,
to achieve efficient wireless resource management.
[0052] Specifically, when the interference ratio meausred by the
monitoring unit 10 exceeds a preset excessive interference ratio,
the control unit 20 may determine that the operation channel has
too much interference, and to resolve the excessive interference,
allow AP to change the operation channel. That is, because the
operation channel being used is excessively influenced by the
non-WLAN signal or interfering signal, AP is allowed to use an
operation channel of another frequency, to resolve the excessive
interference.
[0053] Furthermore, the control unit 20 may determine whether the
overlapping load ratio measured by the monitoring unit 10 exceeds a
preset overlapping ratio limit, and when the overlapping load ratio
exceeds the preset overlapping ratio limit, may determine it as
excessive overlapping load. That is, when the overlapping load
ratio exceeds the overlapping ratio limit, AP may be deficient in
wireless resource utilization due to nearby AP excessively
occupying the operation channel. Accordingly, when it is determined
as excessive overlapping load, the control unit 20 may allow AP to
change the operation channel to avoid OBSS environment.
[0054] As described in the foregoing, when changing the operation
channel, the control unit 20 may receive a wireless resource
distribution matrix of another operation channel from the
monitoring unit 10 beforehand. Subsequently, the control unit 20
may set an operation channel to change based on the received
wireless resource distribution matrix of another channel. For
example, in the case of excessive interference, the control unit 20
may select a channel having a relatively low interference ratio and
change the operation channel to the selected channel, and in the
case of excessive overlapping load, the control unit 20 may select
a channel having a relatively low overlapping load ratio and change
the operation channel to the selected channel.
[0055] Additionally, the control unit 20 may identify whether the
load ratio measured by the monitoring unit 10 exceeds a preset load
ratio limit, and when the measured load ratio exceeds the preset
load ratio limit, may determine it as excessive self-load. That is,
AP having a concentration of stations may fail to exert its normal
performance or may have a risk of WLAN service quality degradation.
Accordingly, to resolve the excessive self-load of AP, the control
unit 20 may hand over STAs connected to AP to nearby APs. That is,
the control unit 20 may distribute the load of AP to other nearby
APs.
[0056] FIG. 6 is a flowchart showing a method for managing wireless
resources according to an embodiment of the present disclosure.
[0057] Referring to FIG. 6, the method for managing wireless
resources according to an embodiment of the present disclosure
includes a monitoring step S100 and a control step S200.
[0058] Hereinafter, the method for managing wireless resources
according to an embodiment of the present disclosure is described
with reference to FIG. 6.
[0059] At the monitoring step S100, AP may monitor the utilization
status of an operation channel being used, and determine the
wireless resource utilization state of the operation channel based
on the monitoring results.
[0060] Specifically, at the monitoring step S100, a wireless
resource utilization distribution matrix of the operation channel
may be generated based on the monitoring results. Here, the
wireless resource utilization distribution matrix may represent a
busy time and an idle time, and the busy time may be the time
during which the operation channel is occupied and used, and the
idle time may be the time during which the operation channel is not
occupied and stays idle waiting. The busy time may include an
interference time, an overlapping load time and a self-load time,
and the interference time may refer to the time during which the
operation channel is occupied by a non-WLAN signal or an
interfering signal, and the overlapping load time may refer to the
time during which nearby AP occupies the operation channel.
Furthermore, the self-load time may refer to the time during which
AP occupies the operation channel.
[0061] Meanwhile, at the monitoring step S100, decoding of a signal
inputted via the operation channel may be performed first, and if
the signal is impossible to decode, the time during which the
signal is inputted may be determined to be the interference time.
That is, because the non-WLAN signal or interfering signal is
impossible for AP to decode, when the signal impossible to decode
is inputted, the operation channel may be determined to be occupied
by the non-WLAN signal or interfering signal. Accordingly, at the
monitoring step S100, the interference time may be calculated by
summing up the time during which detection of energy higher than or
equal to a preset energy limit continues over the total monitoring
time during which monitoring is performed. Generally, because there
is always a non-WLAN signal or interfering signal applied to the
operation channel, only in the case in which the non-WLAN signal or
interfering signal has levels higher than or equal to the preset
energy limit, it may be determined that the non-WLAN signal or
interfering signal occupies the operation channel.
[0062] In contrast, at the monitoring step S100, if the signal
inputted via the operation channel is possible to decode, the
operation channel may be determined to be occupied by AP or nearby
AP. Here, using a transmitter address or a receiver address
included in a header region of a MAC frame included in the signal,
it is possible to determine whether the operation channel is
occupied by nearby AP or whether AP occupies the operation channel.
That is, when the transmitter address or receiver address included
in the decoded MAC header matches an address of a station connected
to AP, the operation channel may be determined to be occupied by
AP, and when the addresses mismatch, the operation channel may be
determined to be occupied by nearby AP. Subsequently, using a
duration value stored in a duration field included in the header
region of the MAC frame included in the signal, it is possible to
identify the time during which the operation channel is occupied by
the signal.
[0063] Accordingly, at the monitoring step S100, the overlapping
load time may be calculated by summing up duration values included
in signals with the transmitter address or receiver address
included in the decoded MAC header mismatching the address of the
station connected to AP, and the self-load time may be calculated
by summing up duration values included in signals with the
transmitter address or receiver address included in the decoded MAC
header matching the address of the station connected to AP.
[0064] Additionally, at the monitoring step S100, the wireless
resource occupany distribution matrix may be generated by
calculating respectively an interference ratio of the interference
time to the total monitoring time, an overlapping load ratio of the
overlapping load time to the total monitoring time, and a load
ratio of the self-load time to the total monitoring time. That is,
the wireless resource occupany distribution matrix may be generated
by applying proportions of the ratios. Meanwhile, at the monitoring
step S100, each corresponding interference time, overlapping load
time, and self-load time in the total monitoring time may be
calculated repeatedly at a preset cycle.
[0065] At the control step S200, AP may change the frequency of the
operation channel or hand over the station connected to AP to
nearby AP, based on the determined wireless resource utilization
state. That is, at the control step S200, wireless resources may be
distributed based on the monitoring results, to achieve efficient
wireless resource management.
[0066] Specifically, at the control step S200, when the measured
interference ratio exceeds a preset excessive interference ratio,
the operation channel may be determined to have too much
interference, and to resolve the excessive interference, AP may be
allowed to change the operation channel. That is, because there is
the excessive influence of the non-WLAN signal or interfering
signal on the operation channel being currently used by AP, AP is
allowed to use an operation channel of another frequency, to
resolve the excessive interference.
[0067] Furthermore, at the control step S200, whether the measured
overlapping load ratio exceeds a preset overlapping ratio limit may
be determined, and when the overlapping load ratio exceeds the
preset overlapping ratio limit, it may be determined as excessive
overlapping load. That is, when the overlapping load ratio exceeds
an overlapping ratio limit, AP may be determined to be deficient in
wireless resource utilization due to nearby AP excessively
occupying the operation channel. Accordingly, through the control
step S200, AP is allowed to change the operation channel so that AP
will be out of overlapping BSS environment.
[0068] Further, at the control step S200, whether the meausred load
ratio exceeds a preset load ratio limit may be determined, and when
the load ratio exceeds the preset load ratio limit, it may be
determined as excessive self-load. That is, as AP has a
concentration of stations, AP may be found to fail to exert its
normal performance or have a risk that the quality of WLAN service
to offer will be degraded. Accordingly, at the control step S200,
to resolve the excessive self-load of AP, stations connected to AP
may be handed over to nearby APs to distribute the load of AP to
other nearby APs.
[0069] The present disclosure is not limited by the aforementioned
embodiments and the accompanying drawings. It will be obvious to
those having ordinary skill in the technical field to which the
present disclosure belongs that substitution, modifications, and
changes would be made to the components of the present disclosure
without departing from the technical concept of the present
disclosure.
* * * * *